A connecting device of the general type of this application is disclosed in EP 0 733 844 B1. In this case, the insert part consists of a single-piece plastic molded part, a dirt seal, which is intended to prevent dust, dirt, moisture (spray water) and the like from penetrating, being molded onto it as a single piece as an encircling sealing lip. Before the pipeline is inserted, this sealing lip extends obliquely radially inward in the insertion direction in such a manner that it is somewhat elastically widened by the inserted pipeline and then rests against it in a sealing manner. For the purpose of being able to release the pipeline, the insert part here has two elastic latching arms which engage with latching attachments into the base part and into latching openings formed there. Each latching arm has an actuating section which protrudes outward from the base part. This known connecting device has essentially been well tried and tested, but, in particular, the dirt seal is still not optimal. In addition, the protruding actuating attachments of the latching arms may be obstructive or may even result in an unintentional release.
The present invention is based on the object of further improving a connecting device of the described generic type in respect of its use properties using economical means.